The present invention generally relates to magnetic recording and reproducing apparatuses employing magnetic tape cassettes and more particularly, to a magnetic recording and reproducing apparatus in which recording and reproduction can be performed on a plurality of kinds of magnetic tape cassettes of different sizes through selective loading of the magnetic tape cassettes.
Generally, a plurality of kinds of magnetic tape cassettes of different sizes are used for magnetic recording and reproducing apparatuses, for example, video tape recorders (hereinbelow, referred to as "VTRs"). Thus, in the case where recording and reproduction are performed on the magnetic tape cassettes of different sizes, VTRs corresponding to the respective magnetic tape cassettes of different sizes are required to be used. Meanwhile, if recording and reproduction on a small magnetic tape cassette is performed by using a VTR for a large magnetic tape cassette, a cassette adapter is employed.
FIG. 1 shows a mechanism 25 of a known VTR for a large magnetic tape cassette 3. In FIG. 1, reference numeral 1 denotes a small magnetic tape cassette 1. When recording and reproduction on the large cassette 3 are performed in the mechanism 25, the large cassette 3 is loaded into a predetermined position and a magnetic tape 3a is drawn from the large cassette 3 by a first pole base 27 and a second pole base 28 so a to be brought into contact with a drum 26, a guide roller 29, an erasing head 33, an audio head 32, etc. The magnetic tape 3a is pressed against a capstan shaft 30 by a pinch roller 31 and the magnetic tape 3a is fed through rotation of the capstan shaft 30. Then, a reel motor (not shown) is driven so as to rotate reels 3b and 3c such that the magnetic tape 3a is wound around the reels 3b and 3c.
Meanwhile, when the small cassette 1 has been loaded into the mechanism 25 so as to perform recording and reproduction on the small tape cassette 1, the cassette 1 itself is small in size, so that it is impossible to draw a magnetic tape 1a from the small cassette 1 by using the first pole base 27 and the second pole base 28 and thus, recording and reproduction on the small cassette 1 cannot be performed. Furthermore, in order to feed the magnetic tape 1a by the capstan shaft 30, the magnetic tape 1a is required to be drawn substantially to the position of the magnetic tape 3a of the large cassette 3, i.e. a position 1a' when the small cassette 1 is loaded into the mechanism 25. In addition, in order to wind the magnetic tape 1a around a take-up reel 1c, it is necessary to provide a mechanism for transmitting a driving force of the reel motor of the mechanism 25 to the take-up reel 1c.
Thus, conventionally, in the case where recording and reproduction on the small cassette 1 are performed by the VTR for the large cassette 3, a cassette adapter 2 is employed as shown in FIG. 2. In FIG. 2, when recording and reproduction on the small cassette 1 are performed by the VTR for the large cassette 3, the small cassette 1 is initially inserted into the cassette adapter 2 in the direction of the arrow a, so that a supply arm 2a and a take-up arm 2b are driven by an adapter motor (not shown) and thus, the magnetic tape 1a engaged with the supply arm 2a and the take-up arm 2b is drawn to the position 1a'. The small cassette 1 has a supply reel 1b and the take-up reel 1c such that the magnetic tape 1a is wound around the supply reel 1b and the take-up reel 1c. The take-up reel 1c is formed, at its hub portion, with a gear in mesh with a driving gear 2c of the cassette adapter 2 and the driving gear 2c is, in turn, engaged with a driving reel 2d. At this time, by inserting the cassette adapter 2 into a cassette control unit (not shown) for the large cassette 3 in the direction of the arrow b, the small cassette 1 is loaded into the VTR and thus, recording and reproduction on the small cassette 1 can be performed. In order to perform winding and rewinding of the magnetic tape 1a, the driving reel 2d and the supply reel 1b are rotated by the reel motor. The small cassette 1 can be removed from the VTR by reversing the preceding steps.
Thus, conventionally, in the case where recording and reproduction on the small cassette are performed by the VTR for the large cassette, it is necessary to use the cassette adapter. Hence, the small cassette is initially inserted into the cassette adapter and the magnetic tape is drawn from the small cassette. Subsequently, the cassette adapter is required to be inserted into the VTR for the large cassette. Furthermore, in the known VTR, such a troublesome operation is required to be performed that the steps of loading are reversed for removing the small cassette.